The present invention relates to a fastening assembly for a roof add-on part of a motor vehicle, wherein the fastening assembly has an outer roof skin element, an outer roof side frame and a roof add-on part fastening element, which has a thread for detachably fastening the roof add-on part.
From DE 102004026773 A1, for example, a fastening means for a roof carrier of a motor vehicle is known. Here, the fastening means is developed at the bottom of a roof gutter that is formed by an outer roof frame body panel and a vehicle roof. A support plate has a projection with an inner thread to which the roof carrier or the like can be fastened. The support plate is, in t connected to the bottom of the roof gutter via a plurality of blind rivets. In particular, the respective blind rivet penetrates a flange of the vehicle roof, as well as the flanges of three body panels of the roof side frame. Fastening openings for fastening the support plate at the bottom of the roof gutter are developed afterwards in the roof gutter. To fasten the support plate, the support plate is positioned with through-openings that align with the fastening openings, the blind rivet is introduced into the respective fastening opening, and in this way, the support plate is fixed at the roof of the vehicle by jamming the flanges of the body panels against each other.
The object of the present invention is to provide a fastening assembly for a roof add-on part of a motor vehicle comprising an outer roof skin element, an outer roof side frame and a roof add-on part fastening element with a thread for detachably fastening the roof add-on part, wherein a production of the fastening assembly is simplified.
This and other objects of the invention are achieved by a fastening assembly for a roof add-on part of a motor vehicle having an outer roof skin element, an outer roof side frame and a roof add-on part fastening element having a thread for detachably fastening the roof add-on part. The roof add-on part fastening element is fastened to a support plate. The support plate is arranged at a flange of the outer roof side frame and is fixed by a blind rivet only at the flange of the outer roof side frame—in particularly jamming the support plate and the flange of the outer roof side frame against each other.
In this way, the roof add-on part fastening element is connected only to the flange of the outer side frame. In particular, the blind rivet only connects e support plate to the flange of the outer roof side frame so that no other aligning through-boring is required in other body panel elements. In this way, a through-boring for the blind rivet can be introduced into the outer roof side frame already even before the outer roof side frame is assembled with the motor vehicle body and, therefore, in particular already before any painting process, without having to take into account production tolerances of other body panel parts and joint tolerances of said body panel parts. A position of the roof add-on part fastening element is therefore determined by the through-boring.
The support plate is in particular developed in a locally limited fashion, which is to say, it reaches only over a locally limited part of the flange of the outer roof side frame. Thus, the width of the support plate preferably corresponds approximately to a width of the flange of the outer roof side frame. The support plate can also be developed a bit wider or a bit less wide than the flange of the outer roof side frame. The support plate can extend in longitudinal direction of the flange over an area that is shorter than a one-digit multiple of the width of the flange.
The blind rivet preferably connects the support plate and the flange by jamming the same against each other.
The roof add-on part, for example, can be a roof carrier for transporting loads and luggage or athletic equipment. In particular, the roof add-on part can be a conventional roof carrier for a passenger motor vehicle.
At least or more roof add-on part fastening elements with a respective associated support plate can be provided at a right outer roof side fame, and correspondingly, two or more roof add-on part fastening elements with a respective associated support plate can be provided at a left outer roof side frame. Preferably, four fastening assemblies are thus provided for the roof add-on part, so that the roof add-on part is connectable to the motor vehicle at at least four points that are spaced apart from each other.
The outer roof side frame and the outer roof skin element preferably form at their interface a groove that runs in longitudinal direction of the vehicle and is also called a gutter.
According to a preferred modification, the roof add-on part fastening element is developed by the blind rivet. In this way, the blind rivet forms a fastener of the support plate at the outer roof side frame as well as a fastening element for the roof add-on part.
According to another preferred modification, the flange of the outer roof side frame has a flange through-boring, and the support plate has a support plate through-boring, with the flange through-boring and the support plate through-boring being in alignment and developed to guide the blind rivet through.
Because the support plate is a locally limited element developed independently of vehicle body elements and has only a supporting function, the support plate through-boring can be arranged particularly easily to align with the flange through-boring. No subsequent boring is required to realize aligning through-borings with narrow tolerances, and the blind rivet can be guided easily through the flange through-boring and the support plate through-boring so that it can connect the flange of the outer roof side frame and the support plate by jamming the same easily into each other.
According to a preferred modification, the support plate is arranged at an inner side of the flange of the outer roof side frame. In particular, the inner side of the flange of the roof side frame is a side that is opposite to an outer side of the car body.
Because of this, the support plate is barely or not at all visible from the outside.
Advantageously, the outer roof skin element of the fastening assembly according to the present invention has a roof flange. The roof flange is connected to the flange of the outer roof side frame. Furthermore, in the area of the blind rivet, the roof flange advantageously has a cutout that is sufficiently larger than the head of the blind rivet.
In this way, the outer roof skin element is connected to the outer roof side frame in a conventional manner, whereas the outer roof skin element does not overlap with the blind rivet because of the cutout in the roof flange. In this way, the blind rivet does not form a positive or non-positive connection between the outer roof skin element and the outer roof side frame.
The cutout can be developed sufficiently large to compensate for production tolerances of the outer roof skin element, wherein the outer roof skin element does not overlap with the blind rivet.
According to a preferred modification, the outer roof skin element is made of a different material than the roof side frame. In particular, the material of the outer roof skin element has a different thermal expansion coefficient than the material of the outer roof side frame. For example, the outer roof skin element can be developed of a light metallic material, in particular an aluminum material or fiber plastic composite material. The outer roof side frame can be developed of a steel material.
Different materials with different thermal expansion coefficients normally lead to problems at the connecting points, wherein with the present invention, there is advantageously no connection between the elements with the various materials and various thermal expansion coefficients, at least not via the roof add-on part fastening element. By selecting a sufficient size of the cutout of the roof flange in the area of the blind rivet, an overlapping of the roof flange and the blind rivet can be avoided over a large temperature range to which motor vehicles may be subjected.
Preferably, the roof flange is joined to the flange of the outer roof side frame by gluing. Is way, the outer roof skin element is glued to the roof side frame.
According to a preferred modification of the fastening assembly, the outer roof side frame and an inner roof side frame together form a roof side frame hollow profile. Thus, a flange of the inner roof side frame is connected to the flange of the outer roof side frame. Preferably, the flange of the inner roof side frame has a cutout in the area of the blind rivet, which is at least larger than a blind rivet bead.
In this way, the flange of the outer roof side frame is principally connected to the flange of the inner roof side frame, but the blind rivet only connects the support plate and the flange of the outer roof side frame. For the blind rivet, in particular the head of the blind rivet, not to overlap with the flange of the inner roof side frame in an assembling of the blind rivet, the flange of the inner roof side frame has the cutout in the area of the blind rivet.
According to further advantageous modification of the fastening assembly according to the present invention, the support plate is arranged between the flange of the outer roof side frame and the flange of the inner roof side frame.
Thus, the support plate can be fixed between the flange of the outer roof side frame and the flange of the inner roof side frame.
The fastening assembly with the outer roof side frame and the inner roof side frame can furthermore have a roof side frame reinforcement that is arranged between the outer roof side frame and the inner roof side frame. Thus, a flange of the roof side frame reinforcement is arranged between the flange of the outer roof side frame and the flange of the inner roof side frame and connected to the flange of the outer roof side frame and the flange of the inner roof side frame. The support plate is arranged between the flange of the outer roof side frame and the flange of the roof side frame reinforcement and the flange of the roof side frame reinforcement can have a cutout that is developed at least sufficiently larger than the blind rivet and/or a blind rivet bead.
In this way, the flange of the roof side frame reinforcement also does not overlap with the blind rivet bead and/or the blind rivet connection.
According to a preferred modification, the support plate is additionally connected in a firm bond to the flange of the outer roof side frame, for example by gluing or welding. Furthermore, the support plate can be additionally connected in a firm bond to the flange of the inner roof side frame and/or the flange of the roof side frame reinforcement, if there is one, for example by gluing or welding.
In this way, the overall fastening assembly is very stable.
According to an especially preferred modification, the blind rivet is developed as a blind rivet nut.
This facilitates an especially easy assembling with few components, wherein an internal thread of the blind rivet nut simultaneously can be the thread for connecting the roof add-on part by use of a screw element.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.